Coastal Environmental Pollution and Fish Species Diversity in Lagos Lagoon, Nigeria.

Rosemary I. Egonmwan; Nnamdi H. Amaeze; Adebayo A. Otitoloju; Adedamola F. Jolaoso
The physical and chemical characteristics as well as the fish species diversity of the coastal fishing grounds of the Lagos lagoon were assessed over a twelve month period. The sampling area was divided into four Zones in line with the established salinity regimes in the area. The sources of pollution in the coast line were found to be widely varied, ranging from chemical inputs and sewage to solid waste. These have caused far reaching effects ranging from foul odour, loss of aesthetics and deterioration in the water quality to reduced fish catch. Overall fish catch was higher in areas closer to river inputs into the lagoon (Zone I and II) where the pollution input was mainly from sewage and diluted effluents. Unregulated burning of sawdust at Okobaba and oil pollution at the ports has led to depleted fish catch in Zones III and IV respectively. Chemical characteristics of the water often fell within the FEPA set limit and there was strong correlation each between chemical oxygen demand (COD), salinity and electrical conductivity of the surface water. Fish diversity significantly varied with sampling Zones (p<0.05) and generally areas receiving organic waste had higher fish diversity compared to those receiving chemical waste.
Waste; Coastal Pollution; Physicochemical Characteristics; Lagos Lagoon; Fish Diversity
Download | Back to Issue| Archive